JP4245015B2 - ORGANIC ELECTROLUMINESCENT DEVICE, METHOD FOR PRODUCING ORGANIC ELECTROLUMINESCENT DEVICE, AND ELECTRONIC DEVICE - Google Patents

Description

  The present invention relates to an organic electroluminescence device, a method for manufacturing an organic electroluminescence device, and an electronic apparatus.

  As a next-generation display device, an organic electroluminescence device (organic EL device) is expected. An organic EL device is configured by disposing an organic EL element having a light emitting layer sandwiched between upper and lower electrodes on a base, typically on a translucent substrate such as glass, an anode, A structure in which an organic functional layer (such as a hole injection layer or a light emitting layer) and a cathode are sequentially stacked is employed. The light emitting layer of the organic functional layer is caused to emit light by supplying current to the organic functional layer through the anode and the cathode.

Organic EL devices are required to improve luminous efficiency. Therefore, Patent Document 1 proposes an organic EL device including an electron transport layer between a cathode and a light emitting layer. This electron transport layer controls the mobility of electrons and efficiently accumulates electrons in the light emitting layer. By providing this electron transport layer, the probability of recombination of holes and electrons in the light emitting layer can be improved, and the light emission efficiency can be improved.
JP 2005-285617 A

  By the way, organic EL devices are roughly classified into those using low molecular organic materials and those using high molecular organic materials. In general, in the case of a low molecular organic EL device, the low molecular organic functional layer is prepared by a dry method such as vapor deposition, and in the case of a high molecular organic EL device, the high molecular organic functional layer is prepared by a wet method such as an inkjet method. . The organic EL device disclosed in Patent Document 1 described above is obtained by vapor-depositing an electron transport layer made of a low-molecular organic material on a polymer light-emitting layer produced by a wet method. However, in an organic EL device having such a high-molecular organic material / low-molecular organic material laminated structure, there is a concern that the transport of electrons at these interfaces is not always good.

  This invention is made | formed in view of such a situation, Comprising: It aims at providing the organic electroluminescent apparatus which improved the electron transport efficiency in the interface of a light emitting layer and an electron carrying layer, and its manufacturing method. . Moreover, it aims at providing electronic devices, such as an organic EL display and an optical printer, which can implement | achieve high-intensity and long lifetime by providing such an organic electroluminescent apparatus.

In order to solve the above problems, an organic electroluminescence device according to a first aspect of the present invention includes an organic electroluminescence device including a first organic layer and a second organic layer formed by a wet method between a pair of electrodes. In the apparatus, the first organic layer includes an organic material having crosslinkability, and has the crosslinkability at least in an interface between the second organic layer and the first organic layer in the first organic layer. A cross-linked layer formed by cross-linking an organic material is provided.
According to this configuration, since the entire organic functional layer including the first organic layer and the second organic layer is formed by a wet method, the transport efficiency of electrons or holes at the interface of each layer can be improved, and the luminous efficiency can be improved. An excellent organic EL device can be provided. In addition, since the first organic layer is formed of a crosslinkable organic material and the second organic layer is insoluble in a solvent that dissolves, the first organic layer is formed even if the second organic layer is formed by a wet method. Can be re-dissolved and a highly reliable organic EL device can be provided.

In the present invention, the first organic layer is a light emitting layer, the second organic layer is an electron transport layer, the light emitting layer includes a light emitting material having crosslinkability, and at least the electrons in the light emitting layer. It is desirable that a cross-linked layer formed by cross-linking the light-emitting material is provided at the interface between the transport layer and the light-emitting layer.
According to this configuration, since the light emitting layer is formed of a light emitting material having crosslinkability, and the electron transport layer is insoluble in the solvent for dissolving, the light emitting layer is regenerated even when the electron transport layer is formed by a wet method. A highly reliable organic EL device can be provided without being dissolved.

In the present invention, the first organic layer is a light emitting layer, the second organic layer is an electron transport layer, and the light emitting layer includes a crosslinkable organic material and a light emitting material, Among them, it is desirable that a crosslinked layer formed by crosslinking the organic material is provided at least at the interface between the electron transport layer and the light emitting layer, and the light emitting material is included in the crosslinked layer.
According to this configuration, the light-emitting layer is formed of a cross-linkable organic material and a light-emitting material, and the electron transport layer is insoluble in a solvent that dissolves. The layer is not redissolved and a highly reliable organic EL device can be provided.

In the present invention, the organic material is preferably a light-emitting material having crosslinkability.
According to this configuration, since the organic material itself contributes to light emission, the light emission efficiency does not decrease even if the organic material is contained.

An organic electroluminescence device according to a second aspect of the present invention is an organic electroluminescence device including a first organic layer and a second organic layer formed by a wet method between a pair of electrodes, The organic layer is formed of an organic material that dissolves in a solvent having a polarity different from that of the solvent that dissolves the second organic layer.
According to this configuration, since the entire organic functional layer including the first organic layer and the second organic layer is formed by a wet method, the transport efficiency of electrons or holes at the interface of each layer can be improved, and the luminous efficiency can be improved. An excellent organic EL device can be provided. In addition, since the polarity of the solvent that dissolves the first organic layer and the polarity of the solvent that dissolves the second organic layer are different from each other, even if the second organic layer is formed by a wet method, the first organic layer is redissolved. And a highly reliable organic EL device can be provided.

An organic electroluminescence device according to a third aspect of the present invention is an organic electroluminescence device including a first organic layer and a second organic layer formed by a wet method between a pair of electrodes, The organic layer is formed of an organic material having relatively low solubility in a solvent that dissolves the second organic layer.
According to this configuration, since the entire organic functional layer including the first organic layer and the second organic layer is formed by a wet method, the transport efficiency of electrons or holes at the interface of each layer can be improved, and the luminous efficiency can be improved. An excellent organic EL device can be provided. In addition, as the solvent for dissolving the second organic layer, a solvent having a low solubility with respect to the first organic layer and a high solubility with respect to the second organic layer was used. Therefore, the second organic layer was formed by a wet method. However, the first organic layer is not redissolved, and a highly reliable organic EL device can be provided.

An organic electroluminescence device according to a fourth aspect of the present invention is an organic electroluminescence device comprising a first organic layer and a second organic layer formed by a wet method between a pair of electrodes, wherein the first The organic layer is a light emitting layer, the second organic layer is an electron transport layer, the electron transport layer includes an electron transport layer forming material having crosslinkability, and the electron transport layer is disposed inside the electron transport layer. A cross-linked layer formed by cross-linking the forming material and a non-cross-linked layer in which the electron transport layer forming material is not cross-linked are provided.
According to this configuration, since the entire organic functional layer including the first organic layer and the second organic layer is formed by a wet method, the transport efficiency of electrons or holes at the interface of each layer can be improved, and the luminous efficiency can be improved. An excellent organic EL device can be provided. In addition, since a part of the electron transport layer, which is the second organic layer, is crosslinked to form a crosslinked layer, the crosslinked layer functions as a hole blocking layer, and the light emission efficiency of the organic EL device can be improved.

In the present invention, the cross-linked layer is provided at an interface between the electron transport layer and the light-emitting layer, and the non-cross-linked layer is formed between the electron transport layer and one of the pair of electrodes. It is desirable to be provided at the interface.
According to this configuration, the cross-linking layer formed at the interface between the light emitting layer and the electron transport layer can efficiently block holes flowing from the light emitting layer to the electron transport layer side, and at the interface between the electron transport layer and the electrode. The formed non-crosslinked layer can promote the transport of electrons into the light emitting layer. For this reason, it is possible to improve the light emission efficiency as compared with the case where all of the electron transport layer forming material is cross-linked or the case where the electron transport layer forming material is not cross-linked at all.

In the present invention, the first organic layer is a light emitting layer, the second organic layer is an electron transport layer, and the electrochemical oxidation potential of the light emitting material forming the light emitting layer is determined by the electron transport layer. It is desirable that it is smaller than the electrochemical oxidation potential of the electron transport layer forming material to be formed.
According to this configuration, the electrons injected into the electron transport layer can be efficiently transported into the light emitting layer, which can contribute to the improvement of the light emission efficiency.

The manufacturing method of the organic electroluminescent apparatus of the 1st form of this invention is a manufacturing method of the organic electroluminescent apparatus which has a 1st organic layer and a 2nd organic layer between a pair of electrodes, The said 1st The organic layer forming step includes a step of disposing a crosslinkable organic material on a substrate and a crosslink of the organic material, so that at least an interface between the first organic layer and the second organic layer And a step of forming a crosslinked layer insoluble in a solvent that dissolves the second organic layer.
According to this method, since the entire organic functional layer including the first organic layer and the second organic layer is formed by a wet method, the transport efficiency of electrons or holes at the interface of each layer can be improved, and the luminous efficiency can be improved. An excellent organic EL device can be provided. In addition, since the first organic layer is formed of a crosslinkable organic material and the second organic layer is insoluble in a solvent that dissolves, the first organic layer is formed even if the second organic layer is formed by a wet method. Can be re-dissolved and a highly reliable organic EL device can be provided.

In the present invention, the first organic layer is a light emitting layer, the second organic layer is an electron transport layer, and in the step of forming the light emitting layer, a light emitting material having crosslinkability is disposed on the substrate. And a step of forming a crosslinked layer insoluble in a solvent that dissolves the electron transport layer at least at the interface between the light emitting layer and the electron transport layer by crosslinking the light emitting material. Is desirable.
According to this method, the light emitting layer is formed of a crosslinkable light emitting material, and the electron transport layer is insoluble in a solvent for dissolving the electron transport layer. A highly reliable organic EL device can be provided without being dissolved.

In the present invention, the first organic layer is a light emitting layer, the second organic layer is an electron transport layer, and the step of forming the light emitting layer includes forming an organic material and a light emitting material having crosslinkability on the substrate. And having a crosslinked structure insoluble in a solvent that dissolves the electron transport layer at least at the interface between the light emitting layer and the electron transport layer by crosslinking the organic material, And a step of forming a cross-linked layer including the light emitting material inside the cross-linked structure.
According to this method, the light-emitting layer is formed of a cross-linkable organic material and a light-emitting material, and the electron transport layer is insoluble in a solvent that dissolves. The layer is not redissolved and a highly reliable organic EL device can be provided.

In the present invention, the organic material is preferably a light-emitting material having crosslinkability.
According to this method, since the organic material itself also contributes to light emission, the light emission efficiency does not decrease even if the organic material is contained.

A manufacturing method of an organic electroluminescence device according to a second aspect of the present invention is a manufacturing method of an organic electroluminescence device having a first organic layer and a second organic layer between a pair of electrodes. The polarity of the solvent that dissolves the organic layer is different from the polarity of the solvent that dissolves the second organic layer.
According to this method, since the entire organic functional layer including the first organic layer and the second organic layer is formed by a wet method, the transport efficiency of electrons or holes at the interface of each layer can be improved, and the luminous efficiency can be improved. An excellent organic EL device can be provided. In addition, since the polarity of the solvent that dissolves the first organic layer and the polarity of the solvent that dissolves the second organic layer are different from each other, even if the second organic layer is formed by a wet method, the first organic layer is redissolved. And a highly reliable organic EL device can be provided.

The manufacturing method of the organic electroluminescent apparatus of the 3rd form of this invention is a manufacturing method of the organic electroluminescent apparatus which has a 1st organic layer and a 2nd organic layer between a pair of electrodes, Said 2nd As a solvent for dissolving the organic layer, a solvent having relatively low solubility with respect to the first organic layer and relatively high solubility with respect to the second organic layer is used.
According to this method, since the entire organic functional layer including the first organic layer and the second organic layer is formed by a wet method, the transport efficiency of electrons or holes at the interface of each layer can be improved, and the luminous efficiency can be improved. An excellent organic EL device can be provided. In addition, as the solvent for dissolving the second organic layer, a solvent having a low solubility with respect to the first organic layer and a high solubility with respect to the second organic layer was used. Therefore, the second organic layer was formed by a wet method. However, the first organic layer is not redissolved, and a highly reliable organic EL device can be provided.

The manufacturing method of the organic electroluminescent apparatus of the 4th form of this invention is a manufacturing method of the organic electroluminescent apparatus which has a 1st organic layer and a 2nd organic layer between a pair of electrodes, The said 1st The organic layer is a light emitting layer, the second organic layer is an electron transport layer, and the step of forming the electron transport layer includes disposing an electron transport layer forming material having crosslinkability on the light emitting layer, By cross-linking a part of the electron transport layer forming material, a cross-linked layer formed by cross-linking the electron transport layer forming material and the electron transport layer forming material are not cross-linked inside the electron transport layer. And a step of forming a crosslinked layer.
According to this method, since the entire organic functional layer including the first organic layer and the second organic layer is formed by a wet method, the transport efficiency of electrons or holes at the interface of each layer can be improved, and the luminous efficiency can be improved. An excellent organic EL device can be provided. In addition, since a part of the electron transport layer, which is the second organic layer, is crosslinked to form a crosslinked layer, the crosslinked layer functions as a hole blocking layer, and the light emission efficiency of the organic EL device can be improved.

In the present invention, in the step of crosslinking the electron transport layer forming material, the light emitting layer, the electron transport layer, and the electron transport layer forming material are caused to undergo a crosslinking reaction from the surface on the light emitting layer side. A cross-linked layer obtained by cross-linking the electron transport layer forming material is formed at the interface, and the electron transport layer forming material is not cross-linked at the interface between the electron transport layer and one of the pair of electrodes. A step of forming a crosslinked layer is desirable.
According to this method, the cross-linked layer formed at the interface between the light emitting layer and the electron transport layer can efficiently block holes flowing from the light emitting layer to the electron transport layer side, and at the interface between the electron transport layer and the electrode. The formed non-crosslinked layer can promote the transport of electrons into the light emitting layer. For this reason, the luminous efficiency can be improved as compared with the case where all of the electron transport layer forming material is cross-linked or the case where the electron transport layer forming material is not cross-linked at all.

The electronic apparatus of the present invention includes the organic electroluminescence device of the present invention described above or the organic electroluminescence device manufactured by the method of manufacturing the organic electroluminescence device of the present invention described above.
According to this configuration, an electronic device with high luminous efficiency can be provided. Examples of such electronic devices include an organic EL display device (organic EL display) including the organic EL device as a display unit, and an image forming device (optical printer) including the organic EL device as a line head. Further, the present invention can be applied to an illumination device (backlight or the like) provided with the organic EL device as a surface light source.

  The present invention will be described below with reference to the drawings. In all the drawings below, the film thicknesses and dimensional ratios of the constituent elements are appropriately changed in order to make the drawings easy to see.

[First Embodiment]
[Configuration of organic EL device]
FIG. 1 is a schematic configuration diagram showing a first embodiment of an organic EL device of the present invention. The organic EL device EL1 includes an anode 3 as a first electrode, a hole injection layer 4, a light emitting layer 5 as a first organic layer, an electron transport layer 6 as a second organic layer, and a second electrode on a substrate 2. The cathode 8 is provided. The hole injection layer 4, the light emitting layer 5, and the electron transport layer 6 are formed of an organic material, and an organic functional layer 7 is formed of these organic layers. The organic functional layer 7 is sandwiched between the first electrode 3 and the second electrode 8, and the organic EL element 9 is formed by the first electrode 3, the organic functional layer 7, and the second electrode 8. Yes.

  A wiring for applying a drive voltage is connected to the first electrode 3 and the second electrode 8. When a driving voltage is applied between the electrodes through this wiring, electrons are injected from the second electrode 8 and holes are injected from the first electrode 8 into the light emitting layer 5, and move in the light emitting layer 5 by the applied electric field. And recombine. The energy released during the recombination generates excitons, and when the excitons return to the ground state, energy is emitted in the form of fluorescence or phosphorescence. The light emitted from the organic EL element 9 is emitted from the base body 2 made of, for example, a glass substrate and taken out to the outside (bottom emission method). In the following description, electrons and holes injected into the light emitting layer may be referred to as carriers.

  Here, as the hole injection layer 4, an arylamine derivative, a phthalocyanine derivative, a polyaniline derivative + an organic acid, a polythiophene derivative + a polymer acid, or the like is used. In particular, a mixture (PEDOT / PSS) of polyethylene dioxythiophene and polystyrene sulfonic acid is suitable.

  The light emitting layer 5 includes a light emitting material having a crosslinkable functional group such as an epoxy group as a light emitting layer forming material (first organic layer forming material). As such a light emitting material, polyfluorene derivatives (PF), polyparaphenylene vinylene derivatives (PPV), polyphenylene derivatives (PP), polyphenylene derivatives (PF), which are known polymer light emitting materials capable of emitting fluorescence or phosphorescence. Paraphenylene derivatives (PPP), polyvinylcarbazole (PVK), polythiophene derivatives, and polysilane-based high molecular organic materials such as polymethylphenylsilane (PMPS) can be preferably used.

  The light emitting layer 5 is a layer insoluble in a solvent by causing such a light emitting material to undergo a crosslinking reaction. For this reason, even if the electron transport layer 6 is formed on the light emitting layer 5 by a wet method, the light emitting layer 5 is not dissolved in the solvent of the electron transport layer 6.

  Examples of the electron transport layer forming material (second organic layer forming material) for forming the electron transport layer 6 include polyfluorene derivatives, polyparaphenylene vinylene derivatives, polyparaphenylene derivatives, polyvinylcarbazole, polythiophene derivatives, polymethylphenylsilane, and the like. A polymer organic material such as polysilane is preferably used.

  The electron transport layer 6 has an electrical reduction potential higher than the electrical reduction potential of the luminescent material forming the light emitting layer 5 in order to efficiently transport the electrons injected from the second electrode 8 to the light emitting layer 5. It is desirable to use a small material. Further, in order to prevent holes injected from the hole injection layer 4 into the light emitting layer 5 from passing through the second electrode side without recombination within the light emitting layer, an electric oxidation potential is generated. It is desirable to use a material that is larger than the electrical oxidation potential of the light-emitting material that forms 5. By doing so, the luminous efficiency can be improved.

  FIG. 2 is a diagram showing a band diagram of the organic EL element 9. In FIG. 2, the LUMO (minimum unoccupied molecular orbital) of the light emitting layer 5 is larger than the LUMO of the electron transport layer 6 so that electrons are efficiently transported from the electron transport layer 6 to the light emitting layer 5. It has become. The HOMO (maximum occupied molecular orbital) of the light emitting layer 5 is smaller than the HOMO of the electron transport layer 6 so that holes injected into the light emitting layer 6 are blocked at the interface with the electron transport layer 6. It has become. Thereby, the electron transport layer 6 functions as an electron transport layer that transports electrons to the light emitting layer 5 and also functions as a hole blocking layer that blocks holes that have entered from the light emitting layer 5.

[Method for Manufacturing Organic EL Device]
Next, a manufacturing method of the organic EL device EL1 will be described with reference to FIG.
First, as shown in FIG. 3A, the hole injection layer 4 and the light emitting layer 5 are formed on the substrate 2 on which the first electrode 3 is formed by using a wet method. As the wet method, a spin coating method, a droplet discharge method, a dip coating method, a roll coating method, or the like can be applied. Among these, the droplet discharge method is preferable because the use of the material is less wasteful and a desired amount of material can be accurately disposed at a desired position.

  Examples of the droplet discharge method (inkjet method) include a charge control method, a pressure vibration method, an electromechanical conversion method, an electrothermal conversion method, and an electrostatic suction method. In the charge control method, a charge is applied to a material by a charging electrode, and the flight direction of the material is controlled by a deflection electrode and discharged from a nozzle. In addition, the pressure vibration method applies an ultra-high pressure to the material and discharges the material to the tip of the nozzle. When the control voltage is not applied, the material moves straight and is discharged from the nozzle, and the control voltage is applied. Electrostatic repulsion occurs between the materials and the materials are scattered and not discharged from the nozzle. In addition, the electromechanical conversion method (piezo method) utilizes the property that a piezo element (piezoelectric element) deforms in response to a pulsed electric signal, and can be used in a space where material is stored by deformation of the piezo element. Pressure is applied through a flexible substance, and the material is pushed out from this space and discharged from the nozzle. In the electrothermal conversion method, a material is rapidly vaporized by a heater provided in a space in which the material is stored to generate bubbles, and the material in the space is discharged by the pressure of the bubbles. In the electrostatic attraction method, a minute pressure is applied in a space in which the material is stored, a meniscus of the material is formed on the nozzle, and an electrostatic attractive force is applied in this state before the material is drawn out. In addition to this, techniques such as a system that uses a change in the viscosity of a fluid due to an electric field and a system that uses a discharge spark are also applicable.

  For the hole injection layer 4, for example, a liquid material containing 3,4-polyethylenedioxythiophene / polystyrene sulfonic acid (PEDOT / PSS) which is a hole injection layer forming material is disposed on the first electrode 3 (20 nm to 100 nm), and this is dried and fired (at 200 ° C. for 10 minutes). As a solvent for the hole injection layer forming material, a polar solvent such as isopropyl alcohol, N-methylpyrrolidone, 1,3-dimethyl-imidazolinone can be used.

  For the light emitting layer 5, for example, a liquid material containing a light emitting material shown in the following [Chemical Formula 1] is disposed on the hole injection layer 4 (50 nm to 200 nm), and this is heat-treated in an inert gas atmosphere such as nitrogen ( For 30 minutes at 130 ° C. to 200 ° C.). The light emitting material of [Chemical Formula 1] is obtained by end-treating a terminal group of poly (9,9-dioctylfluorene) with phenyl epoxide, and the epoxy group of this phenyl epoxide has crosslinkability. As a solvent for the light emitting material, a nonpolar solvent such as toluene that is insoluble in the hole injection layer 4 can be used in order to prevent re-dissolution of the hole injection layer 4.

  In the luminescent material of [Chemical Formula 1], an epoxy group which is a crosslinkable functional group is cross-linked by heat treatment to form a layer (cross-linked layer) insoluble in a solvent that dissolves the electron transport layer 6. Such a layer may be formed on the entire light emitting layer, or may be formed only at the interface between the light emitting layer 5 and the electron transport layer 6. If it is formed at least at the interface between the light-emitting layer 5 and the electron transport layer 6, the light-emitting layer 5 is redissolved in a solvent for dissolving the electron transport layer 6 when the electron transport layer 6 is formed by a wet method. Never happen.

  In [Chemical Formula 1], phenyl epoxide is used as the crosslinkable functional group, but an epoxy group other than phenyl epoxide, a double bond group, or a cyclic ether group may be used. In [Chemical Formula 1], the crosslinkable functional group is introduced into the polymer terminal group, but the crosslinkable functional group may be introduced into the polymer main chain skeleton or the side chain skeleton.

  Next, as shown in FIG. 3B, the electron transport layer 6 is formed on the light emitting layer 5 by using a wet method. For the electron transport layer 6, for example, a liquid material containing an electron transport layer forming material shown in the following [Chemical Formula 2] is disposed on the light emitting layer 5 (5 nm to 50 nm), and this is heated in an inert gas atmosphere such as nitrogen. It is formed by processing (at 130 ° C. for 30 minutes). As the solvent for the electron transport layer forming material, a nonpolar solvent such as toluene can be used. Since the light emitting layer 5 is insoluble in the nonpolar solvent by the above-described treatment, the light emitting layer 5 is not dissolved again in the solvent even if such a liquid material is disposed on the light emitting layer 5. Absent.

  Next, as shown in FIG. 3C, the second electrode 8 is formed on the electron transport layer 6. The second electrode 8 can be formed, for example, by sequentially laminating lithium fluoride, calcium, and aluminum by a vacuum deposition method. As a result, the organic EL element 9 is formed on the substrate 2. Thereafter, a sealing process is performed as necessary to complete the organic EL device EL1.

  As described above, according to the organic EL device EL1 of the present embodiment, since the entire organic functional layer 7 including the light emitting layer 5 and the electron transport layer 6 is formed by a wet method, electrons or holes at the interface of each layer are formed. Transport efficiency can be improved, and an organic EL device excellent in luminous efficiency can be provided. Further, since the light emitting layer 5 is formed of a light emitting material having crosslinkability and the electron transport layer 6 is insoluble in a solvent for dissolving, the light emitting layer 5 is re-applied even when the electron transport layer 6 is formed by a wet method. A highly reliable organic EL device EL1 can be provided without being dissolved.

[Second Embodiment]
[Configuration of organic EL device]
FIG. 4 is a schematic configuration diagram showing a second embodiment of the organic EL device of the present invention. The organic EL device EL2 includes an anode 3 as a first electrode, a hole injection layer 4, a light emitting layer 50 as a first organic layer, an electron transport layer 6 as a second organic layer, and a second electrode on a substrate 2. The cathode 8 is provided. The hole injection layer 4, the light emitting layer 50, and the electron transport layer 6 are formed of an organic material, and an organic functional layer 71 is formed of these organic layers. The organic functional layer 71 is sandwiched between the first electrode 3 and the second electrode 8, and the organic EL element 91 is formed by the first electrode 3, the organic functional layer 71, and the second electrode 8. Yes. Since the configuration other than the light emitting layer 50 is the same as that of the organic EL device EL1 according to the first embodiment shown in FIG. 1, the configuration and the formation process of the light emitting layer 50 will be mainly described here, and other descriptions will be given. Omitted.

  The light emitting layer 50 includes an organic material 51 having a crosslinkable functional group such as an epoxy group and a light emitting material 52 as a light emitting layer forming material (first organic layer forming material). As the light-emitting material 52, polyfluorene derivatives (PF), polyparaphenylene vinylene derivatives (PPV), polyphenylene derivatives (PP), polyparaphenylene, which are known polymer light-emitting materials capable of emitting fluorescence or phosphorescence. Derivatives (PPP), polyvinylcarbazole (PVK), polythiophene derivatives, and polysilane-based polymer organic materials such as polymethylphenylsilane (PMPS) can be suitably used. Further, as the organic material 51, a crosslinkable light emitting material obtained by adding a crosslinkable functional group such as an epoxy group to such a known light emitting material can be used.

  The light emitting layer 50 has such a cross-linking structure that is insoluble in a solvent by causing the organic material 51 to undergo a cross-linking reaction, and becomes a layer (cross-linking layer) including the light-emitting material 52 inside the cross-linked structure. Yes. For this reason, even if the electron transport layer 6 is formed on the light emitting layer 50 by a wet method, the light emitting layer 50 is not dissolved in the solvent of the electron transport layer 6.

[Method for Manufacturing Organic EL Device]
Next, a manufacturing method of the organic EL device EL2 will be described with reference to FIG.
First, as shown in FIG. 5A, the light emitting layer 50 is formed on the substrate 2 on which the first electrode 3 and the hole injection layer 4 are formed using a wet method. For the light emitting layer 50, for example, a liquid material including an organic material 51 made of the organic compound shown in [Chemical Formula 1] and a light emitting material 52 shown in [Chemical Formula 3] below is disposed on the hole injection layer 4 (50 nm). ˜200 nm), which is formed by heat treatment (at 130 ° C. to 200 ° C. for 30 minutes) in an inert gas atmosphere such as nitrogen. The organic material 51 of [Chemical Formula 1] is obtained by terminating a terminal group of poly (9,9-dioctylfluorene) with phenyl epoxide, and the epoxy group of this phenyl epoxide has crosslinkability. As a solvent for the organic material 51 and the light emitting material 52, a nonpolar solvent such as toluene that is insoluble in the hole injection layer 4 can be used in order to prevent re-dissolution of the hole injection layer 4. The mixing weight ratio of the organic material 51 and the light emitting material 52 (organic material 51 / light emitting material 52) can be set to 5% to 500%.

  The organic material 51 of [Chemical Formula 1] forms a layer (crosslinked layer) that is insoluble in the solvent that dissolves the electron transport layer 6 by crosslinking the epoxy group that is a crosslinkable functional group by heat treatment. Such a layer may be formed on the entire light emitting layer, or may be formed only at the interface between the light emitting layer 50 and the electron transport layer 6. If it is formed at least at the interface between the light-emitting layer 50 and the electron transport layer 6, the light-emitting layer 50 is redissolved in a solvent that dissolves the electron transport layer 6 when the electron transport layer 6 is formed by a wet method. Never happen.

  In [Chemical Formula 1], phenyl epoxide is used as the crosslinkable functional group, but an epoxy group other than phenyl epoxide, a double bond group, or a cyclic ether group may be used. In [Chemical Formula 1], the crosslinkable functional group is introduced into the polymer terminal group, but the crosslinkable functional group may be introduced into the polymer main chain skeleton or the side chain skeleton.

  Next, as shown in FIG. 5B, the electron transport layer 6 is formed on the light emitting layer 50 by using a wet method. The forming material and forming method of the electron transport layer 6 are the same as those in the first embodiment. As a solvent for the electron transport layer forming material, a nonpolar solvent such as toluene can be used. Since the light emitting layer 50 is insoluble in the nonpolar solvent by the above-described treatment, the light emitting layer 50 is not dissolved again in the solvent even if such a liquid material is disposed on the light emitting layer 50. Absent.

  Next, as shown in FIG. 5C, the second electrode 8 is formed on the electron transport layer 6. Thereafter, a sealing process is performed as necessary to complete the organic EL device EL2.

  As described above, also in the organic EL device EL2 of the present embodiment, the entire organic functional layer 71 including the light emitting layer 50 and the electron transport layer 6 is formed by a wet method. An organic EL device that can be improved and has excellent luminous efficiency can be provided. In addition, since the light emitting layer 50 is formed of the crosslinkable organic material 51 and the light emitting material 52 and the electron transport layer 6 is insoluble in the solvent for dissolving, the electron transport layer 6 may be formed by a wet method. The light emitting layer 50 is not redissolved and a highly reliable organic EL device EL2 can be provided. Further, since the organic material 51 is provided with a light emitting function, even if the organic material 51 is contained, the light emission efficiency is not lowered and a bright display is possible.

[Third Embodiment]
[Configuration of organic EL device]
FIG. 6 is a schematic configuration diagram showing a third embodiment of the organic EL device of the present invention. The organic EL device EL3 includes an anode 3 as a first electrode, a hole injection layer 4, a light-emitting layer 53 as a first organic layer, an electron transport layer 61 as a second organic layer, and a second electrode on the substrate 2. The cathode 8 is provided. The hole injection layer 4, the light emitting layer 53, and the electron transport layer 61 are formed of an organic material, and an organic functional layer 72 is formed of these organic layers. The organic functional layer 72 is sandwiched between the first electrode 3 and the second electrode 8, and the organic EL element 92 is formed by the first electrode 3, the organic functional layer 72, and the second electrode 8. Yes. The configuration other than the light emitting layer 53 and the electron transport layer 61 is the same as that of the organic EL device EL1 of the first embodiment shown in FIG. The other explanations will be omitted.

  As the light emitting layer forming material (first organic layer forming material) for forming the light emitting layer 53, polyfluorene derivatives (PF), polyparaphenylene, which are known polymer light emitting materials capable of emitting fluorescence or phosphorescence. Suitable organic organic materials such as vinylene derivatives (PPV), polyphenylene derivatives (PP), polyparaphenylene derivatives (PPP), polyvinylcarbazole (PVK), polythiophene derivatives, and polysilanes such as polymethylphenylsilane (PMPS) Can be used.

  Examples of the electron transport layer forming material (second organic layer forming material) for forming the electron transport layer 61 include polyfluorene derivatives, polyparaphenylene vinylene derivatives, polyparaphenylene derivatives, polyvinylcarbazole, polythiophene derivatives, and polymethylphenylsilane. A polymer organic material such as polysilane is preferably used. The electron transport layer 61 is dissolved in a solvent having a different polarity from the solvent in which the light emitting layer 53 is dissolved. Therefore, even if the light emitting layer 53 is not cross-linked, the light emitting layer 53 is not redissolved in a solvent that dissolves the electron transport layer 61.

[Method for Manufacturing Organic EL Device]
Next, a manufacturing method of the organic EL device EL3 will be described with reference to FIG.
First, as shown in FIG. 7A, a light emitting layer 53 is formed on the substrate 2 on which the first electrode 3 and the hole injection layer 4 are formed using a wet method. For the light emitting layer 53, for example, a liquid material containing the light emitting material shown in [Chemical Formula 3] is disposed on the hole injection layer 4 (50 nm to 200 nm), and this is heat-treated in an inert gas atmosphere such as nitrogen ( For 30 minutes at 130 ° C. to 200 ° C.). As a solvent for the light emitting material, a nonpolar solvent such as toluene that is insoluble in the hole injection layer 4 is used in order to prevent re-dissolution of the hole injection layer 4.

  Next, as shown in FIG. 7B, the electron transport layer 61 is formed on the light emitting layer 53 by using a wet method. For the electron transport layer 61, for example, a liquid material containing an electron transport layer forming material shown in the following [Chemical Formula 4] is disposed on the light emitting layer 53 (5 nm to 50 nm), and this is heated in an inert gas atmosphere such as nitrogen. It is formed by processing (at 130 ° C. for 30 minutes). As a solvent for the electron transport layer forming material, a polar solvent such as methanol is used. Since the polarity of the solvent is different from the polarity of the solvent that dissolves the light emitting layer 53, the light emitting layer 53 will not be re-dissolved in the solvent even if such a liquid material is disposed on the light emitting layer 53.

  Next, as shown in FIG. 7C, the second electrode 8 is formed on the electron transport layer 61. Thereafter, a sealing step is performed as necessary to complete the organic EL device EL3.

  Thus, also in the organic EL device EL3 of the present embodiment, since the entire organic functional layer 72 including the light emitting layer 53 and the electron transport layer 61 is formed by a wet method, the transport efficiency of electrons or holes at the interface of each layer is improved. An organic EL device that can be improved and has excellent luminous efficiency can be provided. In addition, since the polarity of the solvent that dissolves the light emitting layer 53 and the polarity of the solvent that dissolves the electron transport layer 61 are different from each other, the light emitting layer 53 is redissolved even when the electron transport layer 61 is formed by a wet method. The organic EL device EL3 with high reliability can be provided.

[Fourth Embodiment]
[Configuration of organic EL device]
FIG. 8 is a schematic configuration diagram showing a fourth embodiment of the organic EL device of the present invention. The organic EL device EL4 includes an anode 3 as a first electrode, a hole injection layer 4, a light emitting layer 53 as a first organic layer, an electron transport layer 6 as a second organic layer, and a second electrode on the substrate 2. The cathode 8 is provided. The hole injection layer 4, the light emitting layer 53, and the electron transport layer 6 are formed of an organic material, and an organic functional layer 73 is formed of these organic layers. The organic functional layer 73 is sandwiched between the first electrode 3 and the second electrode 8, and the organic EL element 93 is formed by the first electrode 3, the organic functional layer 73, and the second electrode 8. Yes. The configurations of the light emitting layer 53 and the electron transport layer 6 are the same as those of the light emitting layer and the electron transport layer described in the first embodiment and the third embodiment.

[Method for Manufacturing Organic EL Device]
Next, a manufacturing method of the organic EL device EL4 will be described with reference to FIG.
First, as shown in FIG. 9A, a light emitting layer 53 is formed on the substrate 2 on which the first electrode 3 and the hole injection layer 4 are formed using a wet method. The forming material and forming method of the light emitting layer 53 are the same as those in the third embodiment. As a solvent for the light emitting material, a nonpolar solvent such as toluene that is insoluble in the hole injection layer 4 is used in order to prevent re-dissolution of the hole injection layer 4.

  Next, as shown in FIG. 9B, the electron transport layer 6 is formed on the light emitting layer 53 by using a wet method. For the electron transport layer 6, for example, a liquid material containing the electron transport layer forming material shown in [Chemical Formula 2] is disposed on the light emitting layer 53 (5 nm to 50 nm), and this is heated in an inert gas atmosphere such as nitrogen. It is formed by processing (at 130 ° C. for 30 minutes). As a solvent for the electron transport layer forming material, a nonpolar solvent having low solubility in the light emitting layer 53 such as xylene is used. Even if the solvent such as xylene is the same nonpolar solvent, it is highly soluble in the electron transport layer forming material shown in [Chemical Formula 2], but in the light emitting material shown in [Chemical Formula 3]. Low solubility. Therefore, even when a liquid material containing a solvent for forming an electron transport layer is disposed on the light emitting layer 53, the light emitting layer 53 is not re-dissolved in the solvent.

  Next, as shown in FIG. 9C, the second electrode 8 is formed on the electron transport layer 6. Thereafter, a sealing step is performed as necessary to complete the organic EL device EL4.

  Thus, also in the organic EL device EL4 of the present embodiment, since the entire organic functional layer 73 including the light emitting layer 53 and the electron transport layer 6 is formed by a wet method, the transport efficiency of electrons or holes at the interface of each layer is improved. An organic EL device that can be improved and has excellent luminous efficiency can be provided. Further, as a solvent for dissolving the electron transport layer 6, a solvent having low solubility with respect to the light emitting layer 53 and high solubility with respect to the electron transport layer 6 was used. Therefore, the electron transport layer 6 was formed by a wet method. In addition, the light emitting layer 53 is not redissolved and a highly reliable organic EL device EL4 can be provided.

[Fifth Embodiment]
[Configuration of organic EL device]
FIG. 10 is a schematic configuration diagram showing a fifth embodiment of the organic EL device of the present invention. The organic EL device EL5 includes an anode 3 as a first electrode, a hole injection layer 4, a light-emitting layer 5 as a first organic layer, an electron transport layer 62 as a second organic layer, and a second electrode on a substrate 2. The cathode 8 is provided. The hole injection layer 4, the light emitting layer 5, and the electron transport layer 62 are formed of an organic material, and an organic functional layer 74 is formed of these organic materials. The organic functional layer 74 is sandwiched between the first electrode 3 and the second electrode 8, and the organic EL element 94 is formed by the first electrode 3, the organic functional layer 74, and the second electrode 8. Yes. Since the configuration other than the electron transport layer 62 is the same as that of the organic EL device EL1 of the first embodiment shown in FIG. 1, the configuration and formation process of the electron transport layer 62 will be mainly described here. Description is omitted.

  The electron transport layer forming material (second organic layer forming material) for forming the electron transport layer 62 includes an electron transport layer forming material having a crosslinkable functional group such as an epoxy group. As such an electron transport layer forming material, a polyfluorene derivative, a polyparaphenylene vinylene derivative, a polyparaphenylene derivative, a polyvinyl carbazole, a polythiophene derivative, a polysilane-based polymer organic material such as polymethylphenylsilane is preferably used. It is done.

  The electron transport layer 62 includes a cross-linked layer 63 formed by cross-linking the electron transport layer forming material inside the electron transport layer 62 by causing a part of the electron transport layer forming material to cross-link, A non-crosslinked layer 64 in which the transport layer forming material is not crosslinked is formed. The cross-linked layer 63 is provided at the interface between the electron transport layer 62 and the light emitting layer 5, and the non-cross-linked layer 64 is provided at the interface between the electron transport layer 62 and the second electrode 8. The ratio of the crosslinked layer 63 in the electron transport layer 62 (crosslink rate of the electron transport layer forming material) is about 50%.

[Method for Manufacturing Organic EL Device]
Next, a manufacturing method of the organic EL device EL5 will be described with reference to FIG.
First, as shown in FIG. 11A, the light emitting layer 5 is formed on the substrate 2 on which the first electrode 3 and the hole injection layer 4 are formed using a wet method. The forming material and forming method of the light emitting layer 5 are the same as those in the first embodiment. The light emitting layer 5 forms a layer (crosslinked layer) insoluble in the solvent that dissolves the electron transport layer 62 by crosslinking the light emitting material of [Chemical Formula 1]. Such a layer may be formed on the entire light emitting layer, or only on the interface between the light emitting layer 5 and the electron transport layer 62. If it is formed at least at the interface between the light-emitting layer 5 and the electron transport layer 62, the light-emitting layer 5 is redissolved in a solvent that dissolves the electron transport layer 62 when the electron transport layer 62 is formed by a wet method. Never happen.

  Next, as illustrated in FIG. 11B, the electron transport layer 62 is formed on the light emitting layer 5 using a wet method. For the electron transport layer 62, for example, a liquid material containing an electron transport layer forming material shown in the following [Chemical Formula 5] is disposed on the light emitting layer 5 (5 nm to 50 nm), and this is heated in an inert gas atmosphere such as nitrogen. It is formed by processing (15 minutes at 150 ° C.). The electron transport layer forming material of [Chemical 5] is the poly [(9,9-dioctylfluorene-2,7-diyl) -alt- (benzothiadiazole-4,7-diyl)] represented by [Chemical 2]. The terminal group is end-treated with phenyl epoxide, and the epoxy group of the phenyl epoxide has crosslinkability. As the solvent for the electron transport layer forming material, a nonpolar solvent such as toluene can be used. Since the light emitting layer 5 is insoluble in the nonpolar solvent by the above-described treatment, the light emitting layer 5 is not dissolved again in the solvent even if such a liquid material is disposed on the light emitting layer 5. Absent.

  In the step of crosslinking the electron transport layer forming material, heat treatment is performed from the base 2 side, and a cross-linking reaction is caused from the surface on the light emitting layer 5 side to the electron transport layer forming material. Then, a crosslinked layer 63 obtained by crosslinking the electron transport layer forming material is formed at the interface between the light emitting layer 5 and the electron transport layer 62, and the electron transport layer forming material is formed at the interface between the electron transport layer 62 and the second electrode 8. A non-crosslinked layer 64 that does not crosslink is formed.

  In the electron transport layer forming material of [Chemical Formula 5], the epoxy group which is a crosslinkable functional group is crosslinked by heat treatment. The cross-linked layer 63 formed at the interface between the light emitting layer 5 and the electron transport layer 62 blocks holes injected from the hole injection layer 4 and contributes to recombination in the light emitting layer 6. On the other hand, the non-crosslinked layer 64 formed at the interface between the electron transport layer 62 and the second electrode 8 does not have a crosslinked structure, and therefore does not hinder the transport of electrons into the light emitting layer 6. Therefore, the luminous efficiency can be improved as compared with the case where the electron transport layer forming material is completely cross-linked or the case where the electron transport layer forming material is not cross-linked at all.

  In [Chemical Formula 5], phenyl epoxide is used as the crosslinkable functional group, but an epoxy group other than phenyl epoxide, a double bond group, or a cyclic ether group may be used. In [Chemical Formula 5], a crosslinkable functional group is introduced into the polymer terminal group, but a crosslinkable functional group may be introduced into the polymer main chain skeleton or the side chain skeleton.

  Next, as shown in FIG. 11C, the second electrode 8 is formed on the electron transport layer 62. Thereafter, a sealing step is performed as necessary to complete the organic EL device EL5.

  As described above, also in the organic EL device EL5 of the present embodiment, the entire organic functional layer 74 including the light emitting layer 5 and the electron transport layer 62 is formed by a wet method. An organic EL device that can be improved and has excellent luminous efficiency can be provided. In addition, since the light emitting layer 5 is formed of a light emitting material having crosslinkability, and the electron transport layer 62 is insoluble in a solvent for dissolving, the light emitting layer 5 is regenerated even when the electron transport layer 62 is formed by a wet method. A highly reliable organic EL device EL5 can be provided without being dissolved. Furthermore, since a part of the electron transport layer 62 is crosslinked to form the crosslinked layer 63, the crosslinked layer 63 functions as a hole blocking layer, and the light emission efficiency of the organic EL device EL5 can be improved. For example, when the crosslinking rate is 50%, the luminous efficiency is improved by 50% compared to the case where the crosslinked layer is not provided.

  In the present embodiment, the light emitting layer 5 has the same configuration as the light emitting layer 5 of the organic EL device EL1 of the first embodiment, but has the same configuration as the light emitting layer 53 of the organic EL device EL2 of the second embodiment. You can also. Any structure can be employed as long as the underlying layer of the electron transport layer is a layer insoluble in a solvent that dissolves the electron transport layer.

[Image forming apparatus]
Next, an image forming apparatus that is a first embodiment of an electronic apparatus including the organic EL device of the present invention will be described. FIG. 12 is a schematic configuration diagram illustrating an image forming apparatus 100 including the organic EL device as a line head.

  The image forming apparatus 100 includes a photosensitive drum 16 as an image carrier in the vicinity of the travel path of the transfer medium 22. Around the photosensitive drum 16, an exposure device 15, a developing device 18, and a transfer roller 21 are sequentially arranged along the rotation direction of the photosensitive drum 16 (indicated by an arrow in the drawing). The photosensitive drum 16 is rotatably provided around the rotation shaft 17, and a photosensitive surface 16 </ b> A is formed on the outer peripheral surface of the photosensitive drum 16 at the central portion in the rotation axis direction. The exposure device 15 and the developing device 18 are arranged in a long axis shape along the rotation shaft 17 of the photosensitive drum 16, and the width in the long axis direction substantially coincides with the width of the photosensitive surface 16A.

  In this image forming apparatus 100, first, in the process of rotating the photosensitive drum 16, the surface of the photosensitive drum 16 (photosensitive surface 16 </ b> A) is positive (for example, positive) by a charging device (not shown) provided on the upstream side of the exposure device 15. Then, the exposure device 15 exposes the surface of the photosensitive drum 16 to form an electrostatic latent image LA on the surface. Further, the toner (developer) 20 is applied to the surface of the photosensitive drum 16 by the developing roller 19 of the developing device 18, and the toner image corresponding to the electrostatic latent image LA is formed by the electric attractive force of the electrostatic latent image LA. It is formed. The toner particles are positively (+) charged.

  After the toner image is formed by the developing device 18, the toner image comes into contact with a transfer medium (not shown) by further rotation of the photosensitive drum 16, and the transfer roller 21 reverses the toner particles of the toner image from the back surface of the transfer medium 22. A polar charge (here, negative (−) charge) is applied, and accordingly, toner particles forming a toner image are attracted to the transfer medium 22 from the surface of the photosensitive drum 16, and the toner image is transferred to the transfer medium 22. Is transferred to the surface.

  The exposure apparatus 15 includes a line head 1 having a plurality of organic EL elements 9 and an imaging optical element 12 having a plurality of lens elements 13 for imaging the light L emitted from the line head 1 at an erecting equal magnification. I have. The line head 1 and the imaging optical element 12 are held by a head case (not shown) while being aligned with each other, and are fixed on the photosensitive drum 16.

  The line head 1 includes a light emitting element array 10 in which a plurality of organic EL elements 9 are arranged along the rotation axis 17 of the photosensitive drum 16, and a drive element group including a drive element (not shown) that drives the organic EL elements 9. And a control circuit group 11 for controlling driving of these drive elements (drive element group). The organic EL element 9, the drive element group, and the control circuit group 11 are integrally formed on a long and thin element substrate (base) 2.

  Here, the organic EL element 9 has the element structure of any one of the embodiments shown in FIG. 1, FIG. 4, FIG. 6, FIG. For this reason, the light emission luminance is high and exposure failure is unlikely to occur.

  The imaging optical element 12 is arranged (arranged) in a zigzag pattern in which the lens elements 13 having the same configuration as the SELFOC (registered trademark) lens element manufactured by Nippon Sheet Glass Co., Ltd. A lens element array 14 is provided.

  In this image forming apparatus 100, since the organic EL element 9 formed on the line head 1 has the above-described structure of the organic EL device of the present invention, the image forming apparatus 100 has a high emission luminance and does not cause poor exposure. Become.

[Organic EL display device]
Next, an organic EL display device which is a second embodiment of an electronic apparatus including the organic EL device of the present invention will be described. FIG. 13 is a schematic configuration diagram of an organic EL display device 200 including organic EL elements as pixels in a matrix.

  The organic EL display device 200 includes a circuit element unit 30 including a thin film transistor as a circuit element, a pixel electrode (first electrode) 3 serving as an anode, an organic functional layer 7 including a light emitting layer, and a counter electrode serving as a cathode. (Second electrode) 8, a sealing portion 32, and the like are provided.

  For example, a glass substrate is used as the substrate 2. As a substrate in the present invention, in addition to a glass substrate, various known substrates used for electro-optical devices and circuit substrates such as a silicon substrate, a quartz substrate, a ceramic substrate, a metal substrate, a plastic substrate, and a plastic film substrate are applied. The

  On the base 2, a plurality of pixel areas A as light emitting areas are arranged in a matrix, and when performing color display, for example, corresponding to each color of red (Red), green (Green), and blue (Blue). Pixel areas A to be arranged are arranged in a predetermined arrangement. In each pixel region A, a pixel electrode 3 is arranged, and in the vicinity thereof, a signal line 42, a common power supply line 43, a scanning line 41, a scanning line for other pixel electrodes (not shown), and the like are arranged. As the planar shape of the pixel region A, an arbitrary shape such as a circle or an oval can be applied in addition to the rectangle shown in the figure.

  The sealing portion 32 prevents water and oxygen from entering and prevents the counter electrode 8 or the organic functional layer 7 from being oxidized, and includes a sealing substrate (or sealing can) 34 bonded to the base 2. The sealing substrate 34 is made of glass, metal, or the like, and the base 2 and the sealing substrate 34 are bonded together with a sealing agent. A desiccant is disposed inside the substrate 2, and an inert gas filling layer 33 filled with an inert gas is formed in a space formed between the substrates.

  In the pixel region A, a first thin film transistor 44 for switching in which a scanning signal is supplied to the gate electrode through the scanning line 41 and a holding for holding an image signal supplied from the signal line 42 through the thin film transistor 44. The capacitor cap, the driving second thin film transistor 45 to which the image signal held by the holding capacitor cap is supplied to the gate electrode, and the common supply line when electrically connected to the common power supply line 43 through the thin film transistor 45 A pixel electrode 3 into which a drive current flows from the electric wire 43 and an organic functional layer 7 sandwiched between the pixel electrode 3 and the counter electrode 8 are provided. The organic functional layer 7 includes a light emitting layer, and the organic EL element 9 which is a light emitting element includes the pixel electrode 3, the counter electrode 8, the organic functional layer 7, and the like.

  Here, the organic EL element 9 has the element structure of any one of the embodiments shown in FIG. 1, FIG. 4, FIG. 6, FIG. For this reason, the luminance is high and bright display is possible.

  In the pixel area A, when the scanning line 41 is driven and the first thin film transistor 44 is turned on, the potential of the signal line 42 at that time is held in the holding capacitor cap, and the second capacitance is changed according to the state of the holding capacitor cap. The conductive state of the thin film transistor 45 is determined. In addition, a current flows from the common power supply line 43 to the pixel electrode 3 through the channel of the second thin film transistor 45, and further a current flows to the counter electrode 8 through the organic functional layer 7. And according to the electric current amount at this time, the organic functional layer 7 light-emits.

  In the organic EL display device 200, light emitted from the organic functional layer 7 to the base 2 side is transmitted through the circuit element unit 30 and the base 2 and emitted to the lower side (observer side) of the base 2. Light emitted from the functional layer 7 to the opposite side of the substrate 2 is reflected by the counter electrode 8, and the light passes through the circuit element unit 30 and the substrate 2 and is emitted to the lower side (observer side) of the substrate 2. (Bottom emission type). Note that light emitted from the counter electrode can be emitted by using a transparent material as the counter electrode 8 (top emission type). In this case, ITO, Pt, Ir, Ni, or Pd can be used as the transparent material for the counter electrode.

  In this organic EL display device 200, since the organic EL element 9 formed in each pixel region A has the above-described structure of the organic EL device of the present invention, the organic EL device has a high light emission luminance and enables a bright display. It becomes a display device.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but it goes without saying that the present invention is not limited to such examples. Various shapes, combinations, and the like of the constituent members shown in the above-described examples are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

  For example, in the organic EL devices EL1 and EL2 of the first embodiment and the second embodiment, the organic compound shown in [Chemical Formula 2] is used as the electron transport layer forming material, but the underlying light emitting layer is the electron transport layer forming material. As long as the layer is insoluble in the solvent, the electron transport layer forming material is not limited to such a material, and the organic compound shown in [Chemical Formula 4] can also be used. Moreover, as long as a light emitting layer is not melt | dissolved in an electron carrying layer forming material, the forming material and forming method of an electron carrying layer can be selected freely.

1 is a schematic configuration diagram of an organic EL device according to a first embodiment of the present invention. It is a figure which shows the band diagram of the organic EL apparatus. It is process drawing explaining the manufacturing method of the organic EL apparatus. It is a schematic block diagram of the organic electroluminescent apparatus which concerns on 2nd Embodiment of this invention. It is process drawing explaining the manufacturing method of the organic EL apparatus. It is a schematic block diagram of the organic electroluminescent apparatus which concerns on 3rd Embodiment of this invention. It is process drawing explaining the manufacturing method of the organic EL apparatus. It is a schematic block diagram of the organic electroluminescent apparatus which concerns on 4th Embodiment of this invention. It is process drawing explaining the manufacturing method of the organic EL apparatus. It is a schematic block diagram of the organic EL apparatus which concerns on 5th Embodiment of this invention. It is process drawing explaining the manufacturing method of the organic EL apparatus. 1 is a schematic configuration diagram of an image forming apparatus that is an example of an electronic apparatus. It is a schematic block diagram of the organic electroluminescence display which is an example of an electronic device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 2 ... Base | substrate, 3 ... 1st electrode, 4 ... Hole injection layer, 5 ... Light emitting layer (1st organic layer), 6 ... Electron carrying layer (2nd organic layer), 7 ... Organic functional layer, 8 ... 2nd Electrode, 9 ... organic EL element, 50 ... light emitting layer (first organic layer), 51 ... organic material, 52 ... light emitting material, 53 ... light emitting layer (first organic layer), 61 ... electron transport layer (second organic layer) , 62 ... Electron transport layer (second organic layer), 63 ... Cross-linked layer, 64 ... Non-cross-linked layer, 100 ... Image forming device (electronic device), 200 ... Organic EL display device (electronic device), EL1 to EL5 ... Organic EL device

Claims (10)

An organic electroluminescence device having a light emitting layer and an electron transport layer formed by a wet method between a pair of electrodes,
The light emitting layer includes an organic material having crosslinkability,
A first cross-linked layer formed by cross-linking the organic material having cross-linkability is provided at least at the interface between the electron transport layer and the light-emitting layer in the light-emitting layer,
The electron transport layer includes an electron transport layer forming material having crosslinkability,
Inside the electron transport layer, a second crosslinked layer formed by crosslinking the electron transport layer forming material, and a non-crosslinked layer in which the electron transport layer forming material is not crosslinked are provided ,
The electron transport layer is formed on the light emitting layer;
The second crosslinked layer is provided at an interface between the electron transport layer and the light emitting layer, and the non-crosslinked layer is disposed at an interface between the electron transport layer and one of the pair of electrodes. An organic electroluminescence device characterized by being provided . Electrochemical oxidation potential of the luminescent material forming the luminescent layer of claim 1, characterized in that less than the electrochemical oxidation potential of the electron transport layer formation material for forming the electron transport layer Organic electroluminescence device. The light emitting layer includes a light emitting material having crosslinkability,
The interface between the light emitting layer and at least the electron transport layer of the light-emitting layer, according to claim 1 or 2, wherein the light emitting material wherein the formed by crosslinking the first crosslinking layer is provided The organic electroluminescent device according to 1. The light emitting layer includes a crosslinkable organic material and a light emitting material,
The first cross-linked layer formed by cross-linking the organic material is provided at the interface between at least the electron transport layer and the light-emitting layer in the light-emitting layer,
The organic electroluminescent device according to claim 1 or 2, characterized in that the luminescent material is contained within said first cross-linking layer. The organic electroluminescent device according to claim 4 , wherein the organic material is a light-emitting material having crosslinkability. A method for producing an organic electroluminescence device comprising a light emitting layer and an electron transport layer formed by a wet method between a pair of electrodes,
The step of forming the light emitting layer includes
Disposing an organic material having crosslinkability on a substrate;
Forming a first crosslinked layer insoluble in a solvent that dissolves the electron transport layer at least at the interface between the light emitting layer and the electron transport layer by crosslinking the organic material,
The step of forming the electron transport layer includes
Disposing an electron transport layer forming material having crosslinkability on the light emitting layer;
A second crosslinked layer formed by crosslinking the electron transport layer forming material inside the electron transport layer by crosslinking a part of the electron transport layer forming material, and the electron transport layer forming material. forming a non-crosslinked layer that does not crosslink, only including,
The step of cross-linking the electron transport layer forming material is caused by causing a cross-linking reaction from the light emitting layer side surface to the electron transport layer forming material, at the interface between the light emitting layer and the electron transport layer. The second cross-linked layer obtained by cross-linking the electron transport layer forming material is formed, and the non-cross-linked material that does not cross-link the electron transport layer forming material at an interface between the electron transport layer and one of the pair of electrodes. A method for producing an organic electroluminescence device, which is a step of forming a crosslinked layer . The step of forming the light emitting layer includes
Disposing a crosslinkable light emitting material on the substrate;
Forming the first crosslinked layer insoluble in the solvent that dissolves the electron transport layer at least at the interface between the light emitting layer and the electron transport layer by crosslinking the light emitting material. The manufacturing method of the organic electroluminescent apparatus of Claim 6 characterized by the above-mentioned. The step of forming the light emitting layer includes
Disposing a crosslinkable organic material and a light emitting material on the substrate;
By cross-linking the organic material, at least an interface between the light-emitting layer and the electron transport layer has a cross-linked structure that is insoluble in a solvent that dissolves the electron transport layer, and the light emission is inside the cross-linked structure. Forming the first cross-linked layer including a material, and manufacturing the organic electroluminescence device according to claim 6 . The method of manufacturing an organic electroluminescence device according to claim 8 , wherein the organic material is a light-emitting material having crosslinkability. The organic electroluminescent device according to any one of claims 1 to 5 or the organic electroluminescent device manufactured by the method for producing an organic electroluminescent device according to any one of claims 6 to 9 is provided. An electronic device characterized by that.

Images